Method of dry cleaning and apparatus therefor



May 16, W39. W. T. REDDISH 2,158,614

METHOD OF DRY CLEANING AND APPARATUS THEREFOR Filed Feb. 17, 1934 2 Sheets-Sheet l INVENTQR WTW ATTORNEY May 16,- 1939. w. T. REDDlSH METHOD OF DRY CLEANINQ AND APPARATUS THEREFOR Filed Feb. 1'7, .934 2 Sheets-Sheet 2 7! III III WM.. 5, a M,

INVENTOR 5 l a f r i ATTORNEY-9' Patented May 16, 1939 UNITED 'STAQTES DIETHOD OF DRY CLEANING AND APPARATUS THEREFOR Warren T. Reddish, Cincinnati, Ohio, assignor, by mesne assignments, to Emery Industries, Inc., a corporation of Ohio (1935) Application February 17, 1934, Serial No. 711,774

18 Claims. (01. 8-142) I This invention relates to a system of dry cleaning, to a method of dry cleaning and apparatus therefor, and, specifically, to an homogenizer adapted to be used in a dry cleaning system of the type disclosed.

The usual dry cleaning process comprises assorting the fabrics to be cleaned into batches in relation to the nature of the fabrics and the degree of soil, then subjecting the batches to suc- 10 cessive treatments with a dry cleaning solvent of the type exemplified by a volatile hydrocarbon or a chlorinated hydrocarbon such as gasoline,

. naphtha, carbon tetrachloride, or trichlorethylene.

straight solvent and are then subjected to a solvent containing a so-called dry cleaning soap,

after which the fabrics are rinsed in straight solvent. The number of treatments may be increased or diminished according to the soil upon the clothes or the efficiency of the apparatus employed.

In a new type of dry cleaning process described and claimed in my Patent No. 1,911,289, water is introduced into the dry cleaning solvent to ef- 5 feet the removal of water spots, water soluble soil, to level the finish on silk or artificial silk fabrics finished with a water sensitive sizing and likewise to renew the vitality of the fiber of woolen fabrics. According to the teaching of the speci- 30 fied patent, an absorbefacient is employed for rendering the cleaning solvent water or moisture absorbent. Throughout the description of my former'patent, and likewise of this patent, the term fabric is used to designate all types of articles normally received by drycleaners; moisture is used to designate a quantityof water which is small in relation to the quantity of dry cleaning solvent employed; and absorbefacient" is used to designate amaterial which suspends 40 or dissolves in the cleaning solvent and endows it with the capacity to hold moisture in dispersed condition.

Preferably, the absorbefacient dissolves in the cleaning solvent and makes it able to take up in- 45 dependently introduced moisture and disperse it to such a degree that the cleaning solvent containing the moisture is substantially optically clear. While this optical clarity is of no benefitin and of itself, still, if the moisture is dispersed 50 to this degree, it is impossible for the moisture to be injurious to the fabrics.

In practicing the moisture process described in my patent, the moisture is introduced in amounts substantially greater than previously.

66 Preferably, the quantity of moisture used ap- Usually the fabrics are given a break in proximates at least 5% of the weight of the fabrics and may be increased in some cases without injury to the fabrics to as high as'30% of the weight of the fabrics. Moreover, it was recommended in said patent that the amount of mois- 5 ture used be determined in relation to the weight and nature of the fabrics being treated. For instance, badly soiled fabrics should be treated with more moisture than slightly soiled fabrics; certain types of woolens, should be treated with a sub- 10 stantially large amount of moisture, but in no case should the amount of moisture employed exceed the moisture tolerance of the fabrics, that is, the amount which would affect the fabrics adversely. 16

The preferred process of practicing the invention of said patent was to introduce the absorbefacient into the cleaning solvent substantially dry, that is, without moisture present, then weigh the batch of fabrics to be cleaned, then disperse 20 the appropriate amount of moisture through the solvent prior to introducing the fabrics. It was found in commercial operations that to incorporate a proper amount of moisture for a given load usually required a concentration of absorbefacient in solvent of between 3 and 6%. Moreover, there was a tendency of the dry cleanerto be careless and not get his moisture thoroughly dispersed before introducing the fabrics. Sometimes the moisture tended to accumulate at some particular point in the solvent line and then flow intothe washer periodically at high concentrations.

The method of dispersing moisture in the cleaning solvent which is disclosed in Patent No. 1,911,289, is primarily a chemical as distinguished from a mechanical method. The present invention involves a mechanical method of mixing moisture with a cleaning solvent.

The moisture instead of being introduced prior to the placing of the load of fabrics to be cleaned in the washer is preferably introduced into the system progressively during the cleaning. The solvent is pumped through a system on the outside of the washer in which a water injector and a homogenizer are disposed. The term homogenizer is used throughout this description to designate a device which mixes and blends the moisture with the solvent containing the absorbefacient and thereby distributes the moisture 5o homogeneously throughout the solvent. The homogeniger may be an atomizlng device, that is, the terminal element of the water injecting device, a high speed mechanical mixing or a device which operates upon the principle of disseminating the waterby a process akin to illtration.

The solvent is pumped from the washer to the homogenizer then back again to the washer. The moisture is introduced into the line of flow of the solvent between the washer and the homogenizer so that the moisture and the solvent are reduced to a uniform consistency by the homogenizer. Preferably, the moisture is added gradually during the cleaning of the fabrics. The fabrics absorb the moisture from the cleaning solvent. The cleaning effect of the moisture on the fabrics is a function of the amount of moisture in relation to the amount of fabrics, not a function of the concentration of moisture in cleaning solvent.

The period of introduction of moisture into the cleaning solvent may therefore comprehend all or any part of the cleaning period. For instance, if

washer, a homogenizer, means for creating a flow of solvent from the washer to the homogenizer and back to the washer again, and means for introducing moisture into the solvent as it flows from the washer to the homogenizer so that the homogenizer disperses the moisture in the solwent.

The invention likewise comprises a novel concept of introducing the moisture into the system slowly and progressively during the cleaning operation at a point outside of the washer and homogenizing the cleaning solvent and moisture prior to returning the cleaning solvent containing the moisture to the washer.

While it is possible, with a sufllciently emcient homogenizer, to practice this invention without the use 01' an absorbefacient or without the use of the usual dry cleaning soap, it is recommended for the sake of safety and for procuring a better cleaning action, that an absorbefacient be employed in the dry cleaning solvent. For instance, the dry cleaning solvent maycontain 1% of an absorbefacient of the type recommended in Patent No. 1,911,289. The formula of the preferred absorbefacient of that patent is as follows:

Oleic acid 25 Naphtha v 25 Pure mahogany sodium sulfonate 50 Instead of an absorbefacient, any one of the several well known dry cleaning soaps on the market may be employed, though these soaps are less powerful and eflective than absorbefacients. If no absorbefacient or soap is used, the homogenizer must be very emcient in order to avoid contacting the fabrics being cleaned with particles of water of substantial size. Conversely, if a strong solution of absorbefacient is employed, the homogenizer need not possess great efilciency. The nature and amount of absorbefacient or soap used must be co-related to the character and efficiency of the homogenizer used to insure a thorough dispersion of moisture in the solvent as it is returned to the washer. The specific homo- Per cent series of minute interstices which break up the moisture into smaller particles, thereby exposing a greater surface of the water to the absorbing action of the solvent containing the absorbefacient.

Preferably the pad is composed of moisture absorbent fibers such as cotton cloth or absorbent cotton. When the pad is first put in use the fibers absorb moisture from the fiow of the cleaning solvent, but, after the fibers are saturated to a certain degree, the cleaning solvent al sorbs moisture from the fibers. In other words, a pan of equilibrium is reached between the fibers of the pad and the cleaning solvent. As stated previously, other types of homogenizers may be used, but the specific type disclosed has the advantage that there are no moving parts or elements churning the solvent at high speed, which action frequently induces charges of static electricity which are at times dangerous. Other types of homogenizers without moving parts may likewise be used, particularly homogenizers operating upon the principle of forcing the cleaning solvent containing the moisture into contact with very large surface areas which have the tendency to break up the moisture and cause it to be absorbed by the solvent.

The more efilcient dry cleaning establishments use filters in connection with the cleaning process and filter the solvent continuously during the cleaning of a batch of fabrics. These filters vary in type and in efflciency, and, likewise, the different filter aids used with the filters are possessed of varying properties. Moisture absorbed in dry cleaning solvent passes some types of filter but not others. Moreover, the pressure developed by the filter varies with the amountof dirt collected on the filter so that moisture may pass a certain type of filter when clean, but not after it has been used a substantial period of time. On this account it is believed to be preferable practice in most installations to place the homogenizer'in the line of flow from the filter to the washer. Otherwise expressed, the solvent is pumped from the washer, to the filter, to the water injector and homogenizer, and then back to the washer.

The apparatus used in the system heretofore set forth for accomplishing the improved meth- 0d of dry cleaning, and the specific homogenizer utilized, are set forth and will be apparent from a description of the accompanying drawings, in which:

Figure 1 is a general view showing the complete system.

Figure 2 is an enlarged detail view of the homogenizer and'the water injector, the homogenizer being shown in section for the purpose of illustrating the internal details thereof.

Figure 3 isa fragmentary view of the needle valve for regulating the flow of the water from the injector into the solvent line.

The, water injector, preferably used, comprises a receptacle adapted to hold a measured amount of water and a needle valve for regulating the fiow of the water into the solvent line or into the homogenizer itself. For convenience this injector is usually attached to the solvent line adjacent to the homogenizer. In view of the fact that the filter disclosed in the present embodiment is of the closed type, the entire system outside of the washer is under pressure, and it is therefore necessary to use an injector of the force feed type. For accomplishing this force feed of the water into the solvent line, the sol-.

vent line is connected to both the top and bottom of the injector, to equalize the pressure so that the water in the injector flows into the solvent line by gravity.

Referring specifically to the drawings, the washer is indicated at 5. This washer may be any one of several well known types. In this case a rotary drum washer is disclosed, incorporating an agitating element indicated at 6. The specific details of the washer are not shown since the present system is of general application.

An outlet pipe 1 extends from the bottom of the washer to the filter 8. A pump 9 is inserted in the outlet pipe 1. No specific disclosure is made of the filter since, as heretofore set forth, it may be any one of several well known types. An outlet pipe in extends from the filter to the homogenizer H and a pipe l2 extends from the homogenizer to the washer 5.

A water injector I3 is connected to the pipe I which extends between the filter and the homogenizer. Preferably, this injector is disposed adjacent to the homogenizer. The injector described in detail is of the following nature. A tank or reservoir i6 is supported on a connecting pipe line indicated generally at l5. This tank includes a conventional gauge I6. In the supporting pipe line an injector valve I1 is incorporated for accurate regulation of the amount of water injected into the pipe l0. As detailed in Figure 3, the operating member I8 of the needle valve is engaged by a spring plate detent l9 for maintaining the operating element in position against accidental displacement after setting.

In view of the fact that the water must be injected into liquid which is under pressure, a device is incorporated for equalizing the pressure at the top of the tank with that in the line or at the outlet end of the injector. For this purpose the supporting or connecting pipe I is of double conduit construction as far as the needle valve; that is to say, an internal pipe extends from the needle valve into the pipe I0 and an external passageway formed by pipe fittings, surrounding the pipe 20, extends to the upper end of the tank. More specifically, the equalizing pipe 2| extends laterally from the external piping below the needle valve and upwardly through the bottom of the tank to the upper region thereof. A valve 22 is placed in this pipe 2|.

An outlet pipe23 extends from" the top of the tank to the atmosphere and is cgntrolled by means of a relief valve 24. This relief passageway and valve permit the operator to completely fill the tank by opening the tank to the atmosphere whereby the air may be expelled therefrom. A gauge 25 is mounted on the tank'and indicates the pressure within the tank and theretrols the flow of water from the supply tank to the main injector. Through this supply tank incorporating a gauge, measured quantities of 'water can be supplied to the tank I l.

The homogenizer is of cylindrical casing structure and is mounted on legs 30. A row of pipes 3| closed at their tops by means of caps 32, are fastened to the bottom of the homogenizer 'tank. The inlet pipe II) to the homogenizer is cut out, formed, and welded against the base of the tank in a position overlying the lower open ends of the pipes 3|; The pipes 3| are perforated as at 33.

An inlet casing structure 34 surrounds the pipes and provides a space 35 to which the outlet pipe I2 is connected. The internal casing structure is perforated as indicated at 36. Filling material 31 is placed within the internal casing wh ch surrounds the pipes 3|. Preferably, the filling 31 is composed of moisture absorbent fibers such as cotton cloth or absorbent cotton. base of the homogenizer connecting to the space 35.

During the operation of the apparatus the pump draws the solvent from the washer and forces it through the filter and past the injector. At this point .the solvent and the added moisture then pass into the tubes 3| of the homogenizer. From these tubes the solvent must pass through the cotton by way of the apertures in the pipes and then through the perforated inner casing into'the space 35 and through the pipe I2 back to the washer. The dispersing, mixing, and blending action, caused by passage through the cotton has been described. i

It will be apparent that as the water leaves the tank, it is replaced by solvent coming in through the equalizing pipe. Therefore, when all the water in the tank has been used, the tank will be completely filled with solvent. At this stage in the operation, the operator closes the needle valve and the valve in the -equalizing pipe and opens the relief valve on the top of the tank. The operator then drains all of the solvent from the tank by way of a-pet-cock H5 at the bottom of the gauge glass.

It is to be understood that the moisture or water which is added in the process hereinbefore described, may be blended, as desired, with other materials which are possessed of special solvent or detergent properties in relation to the soil on the garments or are possessed of properties augmenting the tendency of the water or moisture to disperse in the cleaning solvent. y

In operation, the batch of fabrics is placed in the washer. A measured amount of water appropriate for the size and nature of the batch is placed in the water injector and the solvent is passed through the line as previously described. The invention is characterized by the fact that the water is added continuously at a predetermined, controlled rate during a substantial portion of the cleaning operation. The effect of the added water or dispersed moisture upon the fabrics being cleaned is to remove water soluble soil ing solvent from the washer to the homogenizer and back to the washer, and means for intro- A clean-out plug 38 is placed at the ducing water into the solvent being pumped from the washer to the homogenizer.

2. In a dry cleaning system, a washer, a filter, a water injector, a homogenizer for water and solvent, and means for directing a flow of solvent from the washer to the filter, to the homogenizer and back to the washer, said water injector adapted to add water to the-solvent prior to its introduction into the homogenizer.

3. A dry cleaning system comprising, a washer, a water injector, a'homogenizer' for the water and solvent, means for creating a fiow of dry cleaning solvent from the washer to the injector and homogenizer and back to the washer, said homogenizer comprising finely divided solid material placed in the direct line of the flow of the solvent so that the solvent and injected water must flow through the finely divided solid material before entering the washer.

4. A method of cleaning fabrics, comprising, treating the fabrics in a receptacle with a dry cleaning solvent containing an absorbefacient, removing the solvent continuously from the receptacle during the treatment, injecting water into the solvent removed, homogenizing the solvent and water, and returning the homogeneous solvent and water to the receptacle, the amount of water being used for any batch of fabrics being determined in relation to the weight and nature of the fabrics and not exceeding the moisture tolerance of the fabrics.

5. A dry cleaning apparatus, comprising, a washer, piping for circulating a cleaning solvent from the bottom of the washer to the top of the washer, a pump in said piping, a water injector betweenthe pump and the top of the washer, and a homogenizing device in the piping between the water injector and the top of the washer, said homogenizing device comprising internal perforated elements in connection with the piping at the inlet side of the homogenizing device, and absorbent material surrounding said perforated elements, whereby the moisture laden solvent must pass through the absorbent material as it circulates through the piping for breaking up the water into small particles and accelerating the dispersion thereof in the solvent.

6. The method of dry cleaning which comprises agitating the articles to be cleaned in a bath of moisture absorbent dry cleaning solvent, and adding to said bath over a period of time as the articles are being cleaned a homogenized mixture of moisture absorbent dry cleaning solvent and water.

7. The method of operating a dry cleaning system which comprises homogenizing water in a dry cleaning solvent, introducing said homogenized mixture into a receptacle, and agitating the fabrics to be cleaned in said receptacle until a substantial portion of its water content has been removed by the fabrics. 8. The method of operating a dry cleaning system which comprises passing a stream of dry cleaning solvent successively through a homogenizer, a washer, a filter and then back to said homogenizer and introducing into the cleaning solvent after its removal from the washer and prior to its introduction into. the homogenizer a gradual feed of water, maintaining the flow of solvent at such a rate that the fabrics being cleaned in the washer substantially reduce the water content of the solvent, and regulating the total amount of water fed into the system so that it is within the moisture tolerance of the fabrics being cleaned.

' cleaning 9. A method of cleaning fabrics which comprises introducing water gradually and progressively into a stream of dry cleaning solvent and mechanically homogenizing the water with the solvent, then introducing said homogenized stream into a washer, and agitating the fabrics to be cleaned in said washer.

10. In a moisture process of dry cleaning the method 'ofpreventing abrupt changes in the umformity of the solvent-moisture mixture compris-' ing passing the moisture receptive dry cleaning solvent to which moisture has been added through an homogenizer to homogenize the moisture and the solvent and maintain the desired moisture equilibrium of the dry cleaning system.

11. The art of dry cleaning fabrics comprising agitating the fabrics in a bath of dry cleaning solvent containing dispersed moisture, continuously removing a portion of the solvent, adding thereto sufficient moisture to replace that absorbed by the fabrics in the bath and continuously passing the removed moisture-containing portion through a homogenizer containing an absorbent material of reduced interstitial area, adapted to complete the dispersion and prevent abrupt changes in the uniformity of moisture content throughout the dry cleaning process.

' 12. The method of dry cleaning fabrics which comprises, agitating the fabrics in a bath of dry solvent mechanically homogenizing moisture in dry cleaning solvent to disperse the moisture in the solvent, adding the solvent containing dispersed moisture to said bath while the fabrics are being agitated therein, withdrawing solvent of reduced moisture content from said bath, and continuing said addition and removal until the fabrics have absorbed a quantity of moisture adapted to remove a substantial proportion of the water soluble soil in the fabrics, the total amount of absorbed moisture however not exceeding the moisture tolerance of the fabrics.

13. A method of dispersing moisture in a dry cleaning solvent, said method comprising, incorporating a moisture dispersing agent in said solvent, passing the solvent through a body of finely divided material, and adding water gradually to said solvent prior to its body of material.

14. The method of cleaning fabrics which comprises, treating the fabrics in a bath'of dry cleaning solvent containing dispersed moisture, withdrawing liquid from said bath over a period of time during which said fabrics are being cleaned, adding and homogenizing water into the liquid withdrawn and returning the liquid thus condipassage through said tioned to the bath.

15.,The method of dry cleaning fabrics which comprises, agitating the fabrics in a bath of dry cleaning solvent containing dispersed moisture,

withdrawing liquid from the bath over a period of time during which the fabrics are being cleaned, mechanically homogenizing moisture'in dry cleaning solvent to disperse the moisture in the solvent, and adding gradually to the bath over a period during which the fabrics are being cleaned the dry cleaning solvent containing the dispersed moisture.

16. In the art of cleaning fabrics in a bath concurrently with dry cleaning solvent and a quota of water, the method of introducing the quota of water into the cleaning bath over a period of time during which the fabrics are being cleaned, comprising, introducing a quota of water gradually and progressively into a stream of dry cleaning solvent, homogenlzingto a highly dis persed condition the water in the stream. and'discharging the stream containing this dispersed moisture into the cleaning bath.

17. The process of removing water soluble soil from a batch of fabrics being cleaned in a dry cleaning solvent, which comprises mechanically homogenizing a quota of water related to the weight and nature of the fabrics being cleaned, in dry cleaning solvent in the presence of a dispersing agent suspended in the solvent, then introducing and commingling this homogenized mixture with the dry cleaning solvent in which the batch of fabrics is being cleaned, and agitating the batch of fabrics in the commingled liquids until a substantial proportion of the water con-' tent has been absorbed by the fabrics.

1a. The process of removing water soluble soil from a batch of fabrics being cleaned in a dry cleaning solvent which comprises mechanically homogenizing a quota of water related to the weight and nature of the fabrics being cleaned, with dry cleaning solvent in the presence of a material selected from the group consisting of soaps and absorbefacients, then introducing and commingling this homogenized mixture with the dry cleaning solvent in which the batch of fabrics is being cleaned, and agitating the batch of fabrics in the commingled liquids until a substantial portion of the water content has been absorbed by the fabrics.

WARREN T. REDDISH- 

